Furnace



June 10, 1930. c. H. HALL 1,762,816

FURNACE Filed Feb. 2, 1928 4 sh ts-sh et 1 JP 00 a INVENTOR Q cow/c5 H. HALL ATTORNEY June 10, 1930.

c. H. HALL FURNACE Filed Feb. 2. 192B 4 Sheets-Sheet 2 INVENTOR CORT/CE H HAL L 7 ATTO'RNEY h C. H. HALL June 10, 1930.

FURNACE 4 Shets-Sheet a Filed Feb.

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INVENTOR CORT/CE H. HALL ATTORNEY June 10, 1930.

c. H. HALL mmmcn Filed Feb. 2. 1928 4 Sheets-Sheet 4 INVENTOR CORT/CE H. HALL BY WM ATTORNEY Patented June 10, 1930 UNITED STATES PATENT OFFICE CORTICE H. HALL, OF GLEN ROCK, NEW JERSEY, ASSIGNOR TO DOMESTIC STOKER COMPANY, OF NEW YORK, N. Y., A. CORPORATION OF DELAWARE FURNACE Application filed February 2, .1928. Serial No. 251,246.

The present invention relates to automatic furnaces and has for an object to provide an improvedfurnace having a plurality of burners adapted to be fed from acommon fuel hopper. v

The nature and objects of the invention will be better understood from a description of a particular embodiment thereof, for the purpose of whichdescription reference should be had to the accompanying drawings forming a part hereof and in which Figure 1 is a side view of a duplex furnace constructed in accordance with the principles of the invention,

Figure 2 is afront view of the same showing the feed actuating mechanism,

Figure 3 is a detail plan view ofthe fire pots showing the position of the fuel feeding 1 mechanism, and r Figure 4 is a sectional view of the same The fire pots are arranged at different distaken on the line IV-IV of Fig. 3.

The apparatus shown for the purpose of illustration comprises a fuel ho per 5, a pair of fire pots 6, 'Z of the under eed type and screw conveyors 8, 9 arranged to feed fuel from the hopper 5 to the respective fire pots together with a conveyor 10 for removing as es frombeneath bothfire pots. Preferably a motor 11 is arranged to automatically actuate the two fuel conveyors and the ash conveyor at an adjustable rate. As shown, a fan 13 is secured to the motor'shaft to supply a forced draft through the conduit 14 to the casing 15 surrounding the conveyor screws which casing provides a'flue for the forced draft. v

The shafts ofthe screw conveyors 8, 9 and 10 carry respectively sprocket wheels 16, 17 and 18 connected thereto by suitable clutches l as indicated at 20, 21 and 22 in Fig. 1. The ends of the shafts are square to receive a crank for operation by hand to dislodge'material in case of need. The, sprocket wheels are driven intermittently from the motor shaft bly suitable mechanism. As shown, a sprocket c ain 25 connects the three sprockets and the .shaft of the conveyor 8 carries a ratchet wheel 26 intermittently driven by .a pawl 27"carried by the rocking arm 28 which is rocked by a I" link 29 connected to the crank 30 which in turn is driven by a worm and wheel 30 gearing from the motor shaft 12. A holding pawl 31 prevents backward movement of the ratchet wheel 26. The sprocket chain is ten.- sioned by a spring pressed sprocket wheel 32.

In order that the extent of actuating movement of the ratchet wheel 26 may be varied, an adjustable shield 33 is pivoted on the shaft of the screw 8 and a link 34 operatively connects' the same to a collar 35 adj ustably mounted on the shaft of the conveyor 9 and having a projecting handle '36 to facilitate adjustment thereof. A suitable scale 38 and pointer 39 indicate the position of adjustment of the handle 36 and cam 33 and therefore the rate of feed. p

The two fire pots are positioned relatively close together, the distance between the center lines thereof being less than the outside diameter of the burner plate of either fire pot.

tances from the hopper in order that the conveyors for feeding fuel thereto may lie relatively close together as best shown in Fig. 3. Each fire pot is made up of upper and lower sections the upper sections 40 are six in number and all are similar The lower sections 41- and 42 are of two different shapes and five in number. The sections 42 are formed to extend substantially vertical to a greater height than the sections 41in order to compensate for the tendency of the feed screw to feed thefuel more to the side of the furnace toward which its upper portion turns. The sections 40 are surrounded b an inner annular supporting plate 44 an an outer perforated burner plate 45. The series of perforations 46 of the burner plates 45 extend around the plates except at the portions where said plates join each other as best indicated in Fig. 3. 1

The foregoing description of a particular embodiment is illustrative merely and not intended as defining the limits of the invention.

I claim:

1. A duplex furnace comprising a fuel hopper, a pair of underfeed firep'ots at dif ferent distances from said hopper and closely adjacent each other, a pair of parallel screw conveyors of different lengths arranged to feed fuel from said hopper to said firepots, said firepots being arranged on the same level, one diagonally behind the other and the conveyors being arranged on the same level and closely adjacent side by side to feed equally from said hopper, a conveyor mechanism for removing ashes from beneath both firepots comprising a screw conveyor extending parallel to said first mentioned screw conveyors and an actuating mechanism for the three screw conveyors comprising sprocket wheels secured to the respective conveyors, a sprocket chain engaging the three sprocket wheels, a ratchet wheel secured to one of said sprocket wheels, a motor, means driven by said motor and comprising a pawl arranged intermittentl to actuate sald ratchet wheel, an adjusta le shield arranged to engage said pawl to make the same inoperative during a portion of its reciprocating movement and means for adjusting said shield, substantially as described.

2. A duplex furnace comprising a fuel hopper, a pair of underfeed firepots at different distances from said hopper and closely adjacent each other, a pair of parallel screw conveyors of different lengths arranged to feed fuel from said hopper to said firepots, said firepots being arranged on the same level, one dia onally behind the other and the conveyors eing arranged on the same level and closely adjacent side by side to feed equally from said hopper, a conveyor mechanism for removing ashes from beneath both firepots comprising a screw conveyor extending parallel to said first mentioned screw conveyors and an actuating mechanism for the three screw conveyors comprising sprocket Wheels secured to the respective conveyors, a sprocket chain engaging the three sprocket wheels and means for actuating said sprocket chain.

In testimony whereof, I have signed my name to this specification this 17th day of January, 1928;

C. H. HALL. 

